Unexamined Japanese Patent Application KOKAI Publication No. 2006-128982 discloses a portable telephone comprising construction in which two housings overlap. This portable telephone, when opened in the lengthwise direction for speaking or using an e-mail function, for example, is used as a vertical screen. Moreover, this portable telephone, when folded such that the screen is on top for using a television function, for example, is used as a horizontal screen.